I have some stairs to build, and I am hoping for a few quick tips to make it simpler. The opening in the floor is 11′ 2″ with a wall on one end, and the height from floor to floor is 108″ so I have to put a couple winders in and 2 steps below the winders. However, I am trying to keep the project as simple as possible.

I have access to a 3-axis home-built CNC (no rotational axis),, and lots of woodworking tools, but I am limited in experience and am still a bit intimidated by complex curves and angles. I have therefore limited the winders to the corner, left out the railing (I’ll buy one), and made 2 of the stringers straight.

Is there a way to straighten the external 2 stringers without them not meeting at the corner or becoming several feet wide? I put in the newell post in the internal corner just to make it possible to straighten the left 2 stringers, but that wouldn’t make sense on the right stringers since those will up against the wall.

Is there anything else I can do to make it easier on myself as a first-timer? I am thinking of using plywood to make the stairs, and then cap the stairs and risers with hardwood. If I screw it up, plywood is cheap! I plan to drop the height of each plywood stair by 3/4″ from what the software spits out in the plans, to accommodate the thickness of the treads I’ll add on top. Is that a good idea?

Here’s what I have so far as a design. If it goes well, I may try another one!